According to the bio on publisher Stark House page on this author: John Rex Gearon, better known to readers as John Flagg, was born December 9, 1911 (the oldest of six) in Chicago, Illinois, and educated in Englewood, New Jersey. He began his career in the theater, playwriting in the 1930s. With Louis Bromfield — for whom he worked as a secretary — Gearon co-wrote a Broadway play in 1935 called De Luxe, a story of expatriate Americans living in Paris after World War I, that starred Melvyn Douglas. He published a well-received first novel, The Velvet Well, in 1946 — filmed by Jacques Deray in 1978 as A Butterfly on the Shoulder — followed by a series of thrillers for Gold Medal Books in the 1950s under the name John Flagg. These include six books featuring post-war agent, Hart Muldoon. Gearon died on June 19, 1993 in San Diego.